Can hoist



July 24, 1951- w. A. SCOTT ETAL CAN HOIST 2 Sheets-Sheet 1 Filed April14, 1949 lNVEN TOPS fl ALTBR 59.5001? JQMES E. Cook W w m 9 M u y 24,1951 a w. A. SCOTT ET AL 2,562,066

CAN HOIST Filed April 1949 2 Sheets-Sheet 2 Ilh INVENTOPS TTOPA/EPatented July 24, 1951 2,562,066; 1 CAN noisrj Walter A. ScottandJamesI-E. CoolePoughkeepsle, N. Y., assignors toThe,-;De--Laval=tSeparat0r Company, New Y0rk;, N Y

New Jersey Application- April 14, 194

7 Claims.

This invention relates to mechanical hoists and more particularly tohoists suitable for operation from the vacuum line of a milking machine;

The hoist of the present invention is of. the general type disclosed inan application of Seldon Hall, Serial No. 714,247, filed December 5,1946,.now- Patent No. 2,476,192 granted July 12, 519.49. Its maincomponents are a cable and pulley'arrangement operable from a. milkingmachine vacuum line by a piston in a cylinder, and a control valve whichmay be selectively positinned toconnect thecylinder interior tothevacuumline or to atmosphere, whereby the: free end "of the" cable maybe raisedor lowered, respecttlvely. The pulley arrangement and the cylindercanzswing together about a vertical support.

Thenew hoist, while retaining all of -theoperatingfeatures of the-hoistdisclosed in the above- -noted: application, has been made moreeconomical to'manufacture and easier to assemble and install. Inaddition, the personal injury hazard to the operator has beenpractically eliminated;

An object'of theinvention is to provide a pneumatically operated hoisthaving a minimum number of parts; and which is quick and: easy to as-581111016;

Another object is toprovide a pneumatically operated hoist which can beused with complete safety.

A hoist made in accordance with the invention comprises a hollow rotarysupporting column forming a hoist cylinder which contains afree-floating piston. On the top of. the column isa hollow head which isconnected toandv derives lateral support from a vertical member:projecting upwardly from the head and disposed on the rotation axis ofthe column. The head supports a pair of pulleys, one of which is locatedad- ,jacent therotation axis of the column, and the other of. which isremote from this axis. A cable extends upward from the piston and intothe head, where it passes over the first pulley, and thence outward fromthe rotation axis of the column and over the secondpulley. The endof thecable depending from the second pulley may be provided. with a hook, orthe like, for holding an object to be hoisted. A pipe line communicateswith the interior of the column and has a valve for controlling the flowof an operating fluid, preferably air, through the line to raise andlower thep'iston.

In the preferred construction, the head on the column is provided. withtwo sockets, one of which. is disposed on therotation axis endure.-

' the? neripherypot the: pulley.

,..acorporation.of- V sens-1 a. mass 1 -ceivesthe lateral" supportingmemben The other socket extendsi laterally from the rotation axis: andcommunicates with the interior of'the head-.1 The pulley adiac'ent therotation" axisis located-at least partly within the head and positionedso that the rotation axis and the axis of. the laterally extendingsocket are tangent to In this way, the pulley serves'to'guid'e the cablefrom the piston into theplatera-lly extending socket, so that the partoi "the cable below the. pulley is on the rotation= axis. A hollow armissecuredin. the laterally extending socket, and-the cable extends fromthe socket through. the arm to the second pu-lleyw-hich is mounted onthe outerend of the arm, where it-may be provided-with a'protectivehousing. 5

With this construction, the use of-a rigid piston rodis avoided, and thecylinder for the pistonforms the-verticalsupport of the hoist. Thehead-onthecolumn can be made as a unitary structure: and serves tosupport the pulley system and also" to-give lateral support to thecolumn; through the -vertical supporting member -:conne'ctedto zthehead. Moreover, the cable is completely enclosed; between the piston andthe pulley-=trom which the cabledepen'ds, this en- :closure beingprovided. bythe column, the head and theahollow armon the head.Additionally, (one of-thei ul-leyszis protectively sheathed by the head;itself, and the other pulley may beprovided with a protective housingmounted on the hol- .lowarm For. a'zbetter understaning, of the.invention, referencemay be had to the accompanying drawings, in which:

.., Fig. 1: is a perspective' view of a preferred form -of the newhoist; p

. Fig. .2 is an enlarged vertical sectional view of the-hollowsupporting column, the free-floating 'piston' therein and the head onthe column, and Fig. '3lis a vertical sectional view, on a reduced.scale oi the secondpulley mounted on the hollow-arm.

Referring to the drawings, the hoist comprises ,-a hollow rotarysupporting column l0 forming a ehoist cylinder. At its lower end, thecolumn arests upon. a base 1.0a: having a nipple Hlb for passage of anoperating fluid, preferably air, to and from the interior of the columnthrough the 'base. ;-A, iiange lllc on the base fits closely into thelower end of the column, the column being zr'eleasably secured to thebase by a screw Hld ex- ,tend-ing througha hole in the column: andgthreededvlntothe flange (40c. The latter carries a rubber ring Illecompressed against the inner wall of the column and by which theconnection between the column and its base is sealed.

On the top of the column I is a hollow structure or head II having adepending flange IIa. which fits closely in the upper end of the column.The head II is releasably secured to the column by a screw I Ibextending through the column wall and threaded into the flange Ila. Atits upper end, the head II is provided with a hollow extension or socketIIc disposed on the rotation axis of the column and alined verticallywith a socket III in the base. A setscrew IId on the socket IIc forms aclamping device for releasably securing a vertical member I2 in thesocket. The top of the column derives lateral support from the member I2through the head. I I, the supporting member I2 being held at its upperend by a plate I3 secured to the ceiling and having a stud I 3aprojecting into the member I2. The base I Ila of the column is supportedby a plate I4 having a stud Ma projecting into the socket III Thus,''the column II) is rotatable about the studs I 3a and 14a on a verticalaxis.

Within the column III is a free-floating piston I5 comprising a lowerplate element I5a, a rubber sealing disc I51), and an upper element I 50in the form of a hollow drum, all of which are held together as a unitby acentral pin IGa secured at its upper end to a cable "Iii. The lowerend of the pin Ilia. has a nut Ifib by which the parts 150., I5?) andI50 are clamped against a shoulder on the pin. The side wallof drum IE0is of sufficient length to guidethe' assembled piston and preventsbinding or tilting of the same within the cylinder due to the pull oncable I6.

From the piston I5, the cable I6 extends upward through a horizontalwallIIe'at the bottom of the head and thence into" the interior of thelatter. As shown, the bottom wall He has a central boss I I ,1 providedwith an opening for the cable, whereby the cable is guided on therotation axis'as a further aid in preventing tilting of the piston I5.Within the head II, the cable passes over a pulley II rotatably mountedin a vertical slot I Ig formed between opposed webs It on the head, the'webs serving to support the pulley axle. From pulley II, the cableextends upward and outward through a hollow extension or socket IIjintegral with the head and projecting at an angle to the vertical socketHe. The pulley I1 is so positioned that part of its periphery engaged bythe cable is on the rotation axis while another part engaged by'thecable is on the axis of socket IIa. Thus, the aforementioned axes aretangent to the periphery of the pulley, part of which is located atapproximately the intersection of these axes. A hollow arm I8 isreleasably held at one end in the socket I I7 by means of a clampingdevice or set screw IIk on this socket. On the other or outer end of armI8 is a housing! having a socket I91; in which the arm is releasablysecured by a clamping device or set screw I9b. A pulleyZI] is r0-tatably mounted in the housing I9 with part of the pulley peripherytangent to the common axes of the socket I9a, and the arm I8. The hollowarm I8, which may be a pipe, is supported at its outer portion byparallel braces 2| attached to the axle of pulley 20 and extending alongthe outside of housing I9 to a clamp 22 on the vertical member or pipeI2.

The cable extends from the head socket Ila through the hollow arm I8 andsocket I9a into "housing I9, where it passes over the pulley 20, and;

4 thence downward through the bottom of housing I9. Its free end isconnected to a grapple 23 adapted to fit around the neck of a milk can24 which is to be placed into or removed from a cooler 25. The grapple23 illustrated is of the construction disclosed in S. F. Hallapplication Serial No. 635,181, filed December 15, 1945, now Patent No.2,481,923 granted September 13, 1949. Piston I5 is moved downwardly inthe cylinder I9 to raise the free end of cable I6. The piston ismotivated by a pressure differential in the cylinder or column I9 and,in the embodiment shown, this is derived from the vacuum line 29 of amilking machine. More particularly, the nipple IIlb on the column baseIlla. is connected to a pipe line including a pipe 26 which extendsupwardly from the nipple along the column wall to a valve 21 having atwo-position control handle 2160. In the up position of this handle, thepipe 26 is connected through the valve to a flexible hose 28 extendingwith a substantial amount oi.

slack between the valve and the vacuum line 29. In the down position ofhandle 21a, the pipe 25 is disconnected from hose 28 and connectedthrough the valve to a short duct 21b communicating with the interior ofhousing II. The duct 21b serves to admit atmospheric air into pipe 26and also afiords lateral support for pipe 23 and valve 21. Since valvesadapted to efiect the above connections selectively are well known, itis unnecessary to describe or illustrate the details of valve 21.

The overall height of'the vertical support for the assembled hoist maybe adapted to any ceiling height by cutting pipe I2 to a length suitableto reach from the bottom of socket He in housing II to the plate I3,suflicient clearance having been provided within the upper taperedportion of housing II to permit the pipe I2 to be lowered therein sothat the upper end of the pipe can clear the stud on plate I3. Afterpipe I2 has been placed over the upper stud I3a, it is locked inposition by screw I Id.

In the operation of the hoist when it is desired to lift the milk can24, the cable I6 is affixed to the can, as by means of grapple 23, andthe handle of valve 21 is moved to the up position indicated in Figs. 1and 2. Air is exhausted from the lower end of column Ill beneath pistonI5 through nipple IIlb, pipe 26, valve 21, and hose 28 to the milkervacuum line 29. As a result, atmospheric pressure entering the columnthrough a passage IIm in head wall He acts upon the top of piston I5 tomove the same downward in the column. Cable I6, being affixed to thepiston, is pulled into the column and the free end is thus elevated tolift the can 24. When the piston I5 has moved to the bottom of thecolumn III, the can may be swung in a horizontal plane on the arm I8, itbeing understood that the column Iii, head II and pipe I2 are rigidlyinter-connected and rotate as a unit with the arm I8.

To lower the can 24, the handle of valve 21 is moved to the downposition. Air at atmospheric pressure then flows through duct 21b, valve21, pipe 26, and nipple Illb to the lower end of the column, and theweight of the can operating through cable III will cause piston I5 tomove :upwardly in column I0. Since the only air escape from that portionof column I0 above the piston is through passage I Im, and possiblyaround the loose fit of cable I6 within the hollow boss I, thecompression of air in the upper portion of the column will act to retardthe upward movement of the piston and have a throttling effect so as toprevent the milk can from descending too rapidly. The head flange Ilaserves as a stop for limiting upward movement of the piston in thecolumn.

It will be observed that the improved hoist is of simple constructionand may be quickly and easily assembled. The use of the free floatingpiston eliminates the usual rigid piston rod extending through at leastone head of the cylinder. The hoist cable is completely enclosed exceptfor the depending free end portion to which an article to be raised orlowered is attached. Thus, the personal injury hazard to an operatorfrom accidental contact with the cable has been greatly reduced if not,for allpractical purposes, entirely eliminated. Because of the one-piecehead H, the assembly of the component parts has been greatly facilitatedand it is possible to utilize the hoist cylinder proper as part of therotatable vertical support for the assembled hoist. It is to be notedalso that the pulleys necessary for the operation of the hoist aresubstantially enclosed, thus further decreasing the operator injuryhazard.

We claim:

1. A hoist comprising a hollow column closed. at its lower end, a bottomsupport for the column on which it is rotatable about a vertical axis, ahollow head removably mounted on the upper end of the column, the headhaving a pair of extensions one of which is disposed on said axis andthe other of which is hollow and has an axis extending laterally fromsaid first axis, a member connected to said first extension forsupporting the head laterally, a hollow arm connected to the hollowextension, a pulley mounted in the head and having part of its peripheryat the intersection of said axes, a second pulley mounted on the outerend of the arm, a freefioating piston in the column, a pipe linecommunicating with the interior of the column, a valve in the pipe linefor controlling the flow of an operating fluid through the line to raiseand lower the piston, and a cable extending upwardly from the pistoninto the head, over said first pulley, through the hollow extension andarm, and over the second pulley.

2. A hoist comprising a hollow rotary column open at the top and bottom,a base releasably secured to the bottom of the column and sealedthereto, a bottom support on which the base is rotatable, a pipe lineconnected to the base and communicating through the base with theinterior of the column, a hollow head releasably secured to the top ofthe column, a pulley mounted in the head, a member connected to the headand supporting the head laterally for rotation with the column, an armprojecting from the head at an angle to said member, a pulley mounted onthe arm, a piston in the column, a cable extending upwardly from thepiston into the head, where it passes over said first pulley, and thenceoutward along the arm and over the second pulley, and a valve in saidpipe line for controlling the flow of an operating fluid through theline to raise and lower the piston.

3. For use in a hoist having a hollow rotary supporting column forming ahoist cylinder, a piston in the column, and a cable extending upwardlyfrom the piston, a head for the column, the head comprising a hollowstructure, a pair of sockets on said structure having intersecting axes,one of the sockets opening upwardly for receiving a lateral support forthe head, the second socket extending at an angle to the first socketand communicating with the interior of said structure to receive thecable, and a pulley mounted in said structure and positioned with saidaxes tangent to the periphery of the pulley, the pulley being adapted toengage the cable and guide it from the piston to said second socket.

4. A head for use on a hollow column of a hoist, as defined in claim 3,comprising also a bottom wall having a cable opening for guiding thecable between the piston and the pulley.

5. In combination with a head as defined in claim 3, a hollow arm in thesecond socket and adapted to receive the cable therefrom, and releasableclamps on the sockets engageable with said arm and lateral support,respectively.

6. A hoist comprising a hollow column rotatable about a vertical axisand closed at its lower end, a head on the column, a member projectingupwardly from the head for supporting it laterally, the head having twosockets disposed at an angle to each other, one of the sockets beingdisposed on said axis and receiving said lateral supporting member, ahollow arm in the second socket, a pair of pulleys supported by thehead. one of the pulleys being located adjacent said axis and the otherpulley being remote from said axis, a free-floating piston in thecolumn, a cable extending upward from the piston and into the head,where it passes over said first pulley, and thence outward from saidaxis through said second socket and the arm and over the second pulley,a pipeline communicating with the interior of the column, and a valve inthe pipeline for controlling the flow of an operating fluid through theline to raise and lower the piston.

7. A hoist according to claim 6, comprising also a housing for thesecond pulley on the outer end of the arm.

WALTER A. 86011. JAMES E. COOK.

REFERENCES CITED The following references are of record-in the

